Tailstock turret



Nov. 4, 1969 Filed April 11. 1967 H. P. SPUHLER mms rocx TURRET 2 Sheets-Sheet 1 Nov. 4, 1969 Hjp. SPUHLER 3,475,995

TAILSI'OCK TURRET Filed April 11, 1967 2 Sheets-Sheet 2 Fig.2

United States Patent US. Cl. 77-25 1 Claim ABSTRACT OF THE DISCLOSURE A tailstock turret on lathes wherein a shaft, parallel with the axis of the lathe and mounted for rotation and axial displacement and having a toolhead with a plurality of toolholders disposed in a ring round the axis of the shaft, is provided in a housing. A piston, which is guided for displacement in the housing and is displaceable along the axis of the lathe, is reciprocable by hydraulic pressure and carries a holder in which the toolhead is mounted for rotation. The holder is provided with a locking member whereby the toolhead, together with the shaft, can be locked with respect to the holder. The shaft carries stops which are displaceable along its axis and one of which can come into contact, during the displacement of the shaft, with a setting member of a control valve accommodated in the housing and can actuate the control valve. The control valve controls the supply of hydraulic pressure to the piston.

The invention relates to improvements to tailstock turrets of lathes.

It is an object of the invention to faciliate the operation of the lathe during repetition work. It is often required to drill holes of different widths and depths without altering the setting of the tailstock itself in any way.

With the above and other objects in view which will become apparent from the detailed description below, a preferred embodiment of the invention is shown in the drawings in which:

FIGURE 1 shows a front view of the tailstock with parts in section.

FIGURE 2 shows a sectional view taken on the line II-II of FIGURE 1.

The tailstock 5 is secured, by means of bolts 6 to the lathe bed, not illustrated. A piston rod 8 and a shaft 9 are mounted for displacement parallel with one another in an upper portion 7 of the tailstock, situated at the level of the lathe axis. The piston rod 8, situated in the axis of the lathe, carries, at one end, a piston 10 which is guided with a sealing action in a cylinder 11 and to both sides of which pressure oil may be admitted through two pipelines 12 and 13. One end of the piston rod 8 in FIG- URE 2 is rigidly connected to a housing 14 carried at one end of the shaft 9.

The other end of the shaft 9 in FIGURE 2, projecting beyond the tailstock, is provided with a plurality of longitudinal grooves 15, in which stops 16 are guided for displacement and can be locked. A further stop is formed by a ring 17 which is likewise mounted for displacement on the shaft 9. The portion 7 is provided with two bearing positions 18 in which the shaft 9 is held not only for displacement but also for rotation.

One arm of a two-armed lever 20, pivotally mounted in a recess 19 in the portion 7, engages between the ring 17 and the stops 16. The end of the other arm of lever 20 engages in an eye provided at the end of a valve tappet 21 so that each pivoting of the lever 20 is converted into an axial displacement of the tappet 21. Two valve members 23, 24, carried by the tappet 21, are guided for displacement but with a sealing action in a futher re- 3,475,995 Patented Nov. 4, 1969 cess 22 of cylindrical shape in the portion 7. Apart from the two pressure-oil pipelines 12, 13- already mentioned, two pipe-lines 25, which are connected to one another and lead to an oil sump, and a feed pipe 26, disposed between these two pipelines, lead into the recess 22.

The tappet 21 is extended beyond the recess 22 into a recess 27 in which there is housed a mechanism for actuating the tappet 21 by hand. This provided with a handle 28 which is pivotable out of a position of rest shown in full lines towards the left or right and to which there is secured a toothed sector which is rotatable about the pivotal axis 29 of the handle. A rack 30, mounted for displacement in the recess 27 engages the toothed sector. Two extensions on the rack act on two discs 31 mounted loosely for displacement on the tappet 21. Between the two discs is a compression spring 32 which is secured to the tappet at its center and by means of which the discs 31 are urged towards the extensions of the rack 30.

The toolhead 33, which is keyed to the shaft 9 by means of a key 36, is mounted for rotation in the housing 14. At its end face, it is provided with as many recesses 34 for toolholders 35 as there are grooves 15 provided on the shaft 9. At the rear, the toolhead 33 carries a spur wheel 37 in which there can engage a toothed lever 38 mounted for pivoting in the housing. A handle 39, which is coupled to the lever 38 in a manner not illustrated, is pivotally mounted at the top of the housing 14. In the normal position of this handle, the lever 38 engages the gearwheel 37 and locks the toolhead 33 against rotation. If the handle 39 is actuated, however, the lever 38 comes out of engagement with the gearwheel 37 as a result of which the toolhead 33 is released for rotation. It can now be turned by hand into a working position in which another toolholder 35 is in the axis of the sleeve.

The mode of operation of the tailstock turret described is as follows. Let it be assumed that a bore of predetermined depth is to be executed by means of a drill 40 inserted in the toolholder 35 situated in the axis of the sleeve. Then the stop 16, which as shown in FIG- URE 2 lies in the path of the lever 20, is set at a distance from the latter corresponding substantially to this depth. The fine adjustment is effected by adjusting the screw 41 on the stop. The handle 28 is now turned towards the right as a result of which the right hand one of the two discs 31 in FIGURE 2 is displaced through the rack 30. In the course of this, the disc entrains the tappet 21 and hence the two slides 23, 24, through the spring 32. The slide 24 brings the return pipeline 25 into communication with the pipeline 13 whereas the slide 23 brings the feed pipe 26, carrying the pressure oil, into communication with the pipeline 12. The pressure oil flowing into the piston compartment 11 now displaced the piston rod 8 and hence also the housing 14 and the toolhead 33 carried thereby so that the tool 40 is displaced towards the workpiece, not illustrated, driven by the lathe.

After penetration of the drill 40 to the set depth, the screw 41 comes to bear against the lever 20 and pivots this in clockwise direction because the supply of pressure oil to the piston compartment 11 still continues. The tappet 21 is displaced towards the right as a result and restores both the slides 23, 24 and also the handle 28 to the position of rest illustrated in FIGURE 2 in which the supply of pressure oil to each of the two sides of the piston 10 is interrupted so that this remains stationary. By setting the handle 28 over towards the left, a displacement of the piston rod 8 towards the right can be caused in the same manner as described above. During this displacement, as soon as the ring 17 impinges on the lever 20, the ring pivots the lever in counter-clockwise direction and so likewise restores the slides 23, 24 to the position of rest.

If the bore efiected in the manner described is then to be made deeper, for example with a smaller width, the handle 39 is pivoted so as to release the locking of the toolhead 33. Thereupon, this is turned by hand into that position in which the tool adapted for executing the fresh bore comes into the axis of the lathe and hence also into the axis of the piston 8. When the stop 16 associated with this tool has been set to the required distance from the lever 20, the bore can be executed by positioning the handle 28 in the manner already described.

I claim:

1. A tailstock turret device for a lathe comprising a tailstock having a bore extending parallel to a working axis, a tool-holder of substantially cylindrical shape having a front face adapted to hold a number of angularly spaced tools, an axle journaled in said bore of said tailstock for axial and rotary movement, said axle being fixed to said toolholder, a casing forming a bearing for said toolholder, said toolholder being rotatable in said bearing to selectively move a tool in alignment with said working axis, said casing having a rear base in which said axle is rotatably journaled, hydraulic shifting means for said casing comprising a cylinder in said tailstock extending coaxially with said working axis, an operating member guided in said cylinder, a piston supported by said operating member adapted to be moved by fluid pressure in said cylinder, said operating member being fixed to said rear base, locking means adapted to releasably lock said toolholder against rotation in said casing, said locking means including a gear wheel fixed to said toolholder disposed in said casing between said toolholder and said rear base and a manually operable latch adapted to engage said gear wheel.

References Cited UNITED STATES PATENTS 2,423,367 7/1947 Bolender 29-42 X 2,783,664 3/1957 Johnson 77-25 3,119,170 1/1964 Buck 29-42 FRANCIS S. HUSAR, Primary Examiner US. Cl. X.R. 

